SANFORD — You don't have to have seen the James Cagney film Public Enemy to enjoy Kenneth Branagh's play of the same name. But there are so many references to the film in both character and plot that a pre-play trip to the video store might be a wise move. The play, an homage to Cagney and an intimate look at the violence in Ireland, is running at Seminole Community College.

Unfortunately, a look at the current news from Britain may help deepen the experience too - as the violent conflict has exploded back to life after more than 18 months of uneasy cease-fire.

Branagh's play is set in Belfast, Northern Ireland, in the turbulence of the '80s when violence and unrest tore into the fabric of the city.

Seminole's production, directed by Sara Z. Daspin, is stark and powerful, with an ensemble of passionate actors led by T.J. Tolbert, who plays Tommy Black, a small-time song-and-dance-man obsessed with Jimmy Cagney, and Mark Smith, portraying Thompson, the police detective with his own obsessions.

The play is part police procedural, part musical, part political commentary and part homage to Cagney films. And it works on all levels, combining the tragic with the humorous to great effect.

Fast-paced scene changes (there are 42 scenes in the play) are accomplished economically with lighting indicating change of place on the simple, stark set.

Tolbert is superb, tap dancing and posturing his way through Black's initially shallow but ultimately complex character.

Black is part of a generation of Irish youth stunned by violence, wearied by constant unemployment, embittered and bored by a life that offers no hope for the future. The ''troubles'' offer something to be passionate about, something active, a cause.

The audience is quite convinced by Black's swaggering and strutting and is fooled, for most of the play, into thinking him a shallow, self-centered oaf. Tolbert skillfully handles the final transition when we learn the complex depths of Black's commitment to changing the horror that Belfast has become.

Smith is excellent as the dogged investigator who has the difficult position of being both narrator and character in this complex piece. Smith chats quietly with the audience, head cocked in anticipation of insight as he fills us in on Thompson's reasoning. His portrayal is beautifully understated, controlling the pace at which the audience is allowed to uncover the truth behind the blustering bravado in Black's character.

''Why do people watch old movies?'' he muses, as he tries to solve a murder with no apparent motive. He rents a copy of Public Enemy, Black's favorite film, and as he watches it, he slowly becomes aware of Black's ambitious purpose.

We first meet Black when he's taking part in a talent contest in a ''wee hall'' in the Protestant sector of Belfast. Tolbert's impression of Cagney transcends the all-too-familiar ''You dirty rat'' level and extends into the way he dances, the way he holds his body when he struts, all pointy toes and light-on-his-feet skipping through the ''Yankee Doodle Dandy'' number. And he slips flawlessly back and forth from Black's slight Irish inflection to the Cagney patter.

Most attempts at accents, which can be problematic in any production with inexperienced actors, have wisely been eliminated in this production. The actors either speak in their normal voices or use subtle inflection, thus avoiding the pitfall of sounding like an Irish Spring commercial. While it makes one wish to see the play done by Irish actors - because it would make the American slang more effective - the decision not to go with heavy brogues was a solid one.

The song-and-dance numbers are entertaining - from Tolbert's ''Yankee Doodle Dandy'' to Jenny Strickland's delightfully funny rendition of a classic American country song. Strickland is spunky as Kitty Rogers, the girl Black loves.

Sam Martin and Mary Higgins Juravle are effective as Black's brother and mother, as are Mik Jacobs and Julio Iglesias as a club owner and a video store owner. Roderick B. Gorby plays a mean piano for the club scenes.

Fred Urfer is waiflike as Black's devoted friend, Davey Boyd, who is also fooled by Black's exaggerated gangster bravado. One of Urfer's last lines, uttered just before tragedy strikes, provides a poignant truth: ''This isn't the movies, Tommy; this is real life.''

And real life, in Black's Belfast in the '80s, as in Cagney's Chicago in the '30s, is obsessed with death.